Nosepiece for microscopes



1941- c. H. 0., WITTIG NOSEPIECE FOR MICROSCOPES Filed July 21, 1939CARL. 5.0. WITT!G Patented Nov. 1 8, 1941 NOSE-PIECE FOR MICROSGOPESCarl H. O. Wittig, Irondequoit, N. Y., assignor to Bausch & Lomb OpticalCompany, Rochester, N. Y., a corporation of New York Application July21, 1939, Serial No. 285,741

2 Claims.

The present invention relates to microscopes and more particularly tonosepieces for carrying a plurality of objective lenses.

One of the objects of the present invention is to provide a microscopenosepiece which is simple in construction yet rigid, accurate and smoothin operation. Another object is to provide a rotary microscope nosepiecein which any wear in the pivot may be taken up and the op eration of thenosepiece kept uniform at all times. Still a further object is toprovide a microscope nosepiece with a new and improved latch mechanismfor releasably holding 'a selected objective in operative position.These and other objects and advantages reside in certain novel featuresof construction, arrangement and combination of parts as willhereinafter be more fully set forth and pointed out in the appendedclaims.

Referring to the drawing:

Fig. 1 is a perspective view of a microscope carrying my new nosepiece.

Fig. 2 is a vertical section of a preferred form of my nosepiece.

Fig. 3 is a section taken on line 33 of Fig. 2.

Fig. 4 is a fragmentary side elevation of the latching means.

Fig. 5 is a section taken on line 55 of Fig. 4.

Fig. 6 is an enlarged fragmentary section of a modified form of pivot.

In the drawing, my new nosepiece is shown in connection with aconventional microscope having a base [0, arm ll, body tube 12 and stageI3. The usual coarse and fine adjustment knobs I4 and I5, respectively,serve to focus the microscope. The nosepiece indicated generally at [6,is secured to the body tube 42 and carries a plurality of objectives [1.

My new nosepiece consists of a fixed part 23 which is rigidly fastenedto the body tube l2 or some other suitable part of the microscope. Inthe embodiment shown in Fig. 2, the fixed part is fastened to themicroscope by an annular sleeve 2| Which extends through the aperture 22of a boss 23 and is held against removal from the part 2!! by a flangeor shoulder 24. The outer end of the sleeve 2| is threaded at 25 forengagement with a corresponding threaded portion of the microscope. Ofcourse, other forms of fastening means may be used without affecting theoperation of my nosepiece.

The fixed part 26 is formed with a central stud 26 on which is threadeda cylindrical pivot sleeve 21. A flange 28 on the sleeve 21 seatsagainst the fixed part 26. A bearing sleeve 29 is rotatably on the.pivot 21 and is internally chamfered at each end to provide theinclined bearing .surfaces 30 and 3!. A plurality of :ball bearings 32surround the pivot 21 and are held against the pivot 21 and flange 28 bythe hearing surface 30 of the sleeve 29. A second row of ball bearings.33 .encircle the pivot 21 and rests'against .the bearing surface 31 ofthe sleeve 29. This second row of ball bearings 33 is held in place by awasher 34 which is preferably fixed against rotation on the pivot sleeve21 by flattening a portion 35 of the pivot 21 and providing acorresponding flattened portion 36 in the aperture of the washer 34.

The bearings and bearing surfaces are protected from dust and dirt by acap 38 which bears against the washer 34 and is held in place by a screwor bolt 39. This screw 39 extends through both the dust cap 38 andwasher 34 and is threaded into the pivot sleeve 21. Any wear in thebearings or bearing surfaces or any looseness between the sleeve 29 andpivot 21 can be taken up by tightening this screw 39.

In the event that more complete dust protection is necessary, I haveprovided the construction shown in Fig. 6. Here the screw 39 engages thewasher 34 directly. The sleeve 29 is made thicker and is threaded toreceive the dust cap 38. In this modification, the screw 39, washer 34and bearings 33 are entirely shielded from dust and dirt.

The bearing sleeve 29 is threaded to receive a rotary objective carrier40 which is formed with a plurality of threaded holes 4! for holdingdifferent objectives 11. These different objectives l1 may beselectively brought into alignment with the attaching sleeve 2| byrotating the carrier 40 and sleeve 29 on the pivot 21. If desired, thefixed part 26 or carrier 42 may be formed with aflange 42 to prevent orreduce the entrance of dust between the fixed part and carrier.

The outer surface 43 of the objective carrier is rounded and is formedwith a slight bulge or raised portion 44 adjacent each threaded hole 4|.A notch 45 is formed in each portion 44 and these notches 45 bear afixed predetermined relation to the adjacent objective mounting hole 4|.A resilient spring arm 46 is fastened to the boss 23 by screws 41 andprojects downward over the surface 43 of the carrier 40. This arm 46 isformed with a recess or pocket 49 in which a roller bearing 48 isloosely mounted. This bearing 48 is in rolling contact with the surface43 of the carrier 40 and engages in the notches 45 to latch theobjectives I! in proper operative position. The rolling friction of thisbearing 48 is not sufficient to injure or destroy any paint or platingon the surface 43. Of course, the surface 43 of the carrier 40 may havea cylindrical contour but I prefer it to have a contour of a frustum ofa right cone.

From the foregoing it will be apparent that I have provided a smooth,rigid and accurate microscope nosepiece which can be maintained in itsoriginal precise and accurate condition throughout a long period of use.Various modifications can, of course, be made without departing from thespirit of my invention or the scope of the appended claims.

I claim:

1. A microscope nosepiece comprising a fixed part, means for securingsaid fixed part to a microscope, a second part rotatably mounted on saidfixed part and carrying a plurality of objectives any one of which maybe moved into operative relation to said fixed part by rotation of saidsecond part, said second part having a rounded exterior surface and aplurality of notches in said surface, one for each objective, aresilient arm secured'to said fixed part and extending over the exteriorsurface of said second part, and a freely rotatable and relativelyelongated roller bearing carried by said arm and contacting saidsurface, said bearing element riding freely over said surface andserving as a detent to engage said notches.

2. A microscope nosepiece in which an objective carrier having a roundedexterior surface is rotatable on a pivot secured to a fixed part of saidnosepiece, said objective carrier slidably mounted on said pivot foradjustment towards said fixed part and provided with means for receivinga plurality of objectives adapted to be moved into operative positionwith said fixed part by rotating the carrier, said rounded surfaceprovided with a plurality of relatively elongated notches, one for eachobjective, the combination of latch means for securing said objectivecarrier in any one of its operative positions with respect to said fixedpart, said means comprising a resilient arm secured to said fixed partand overhanging said surface of said carrier, said arm having arelatively elongated recess adjacent said surface of said carrier, and aroller bearing of a length substantially equal to said recess positionedtherein to be freely rotatable and to contact said surface, said bearingadapted to engage in said notches and releasably hold said carrieragainst rotation.

CARL H. O. WITTIG.

